my work from home mess-up

so i was working from home like normal and everything is going well i mean it was but then my client wanted a super last minute change to the project due today which is literally impossible for me to do in time no way man so i sent them an email saying idk how bout next week they need till next week its not realistic but they are not happy at all and now they want to cancel the whole thing and find someone else who can do it on such short notice which im not sure exists anyway but still omg i feel so bad like i totally understand why theyre upset but this is literally impossible for me without doing something illegal or completely unethical and now im worried about getting paid and losing a client over this stupid last minute thing i really dont want that to happen. oh and also my cat got into some paper and shredded it all like it was nap time so thats adding stress too. not the best day lol